01 - Lay out all bread slices. Spread a thin layer of softened butter on one side of each slice.
02 - Flip two slices buttered side down. Spread 1 tablespoon marinara sauce on each slice.
03 - Sprinkle half the mozzarella cheese evenly over the sauced bread slices.
04 - Arrange pepperoni slices over the mozzarella layer.
05 - Sprinkle remaining mozzarella and half the Parmesan over the pepperoni.
06 - Top each with remaining bread slices, buttered side facing up.
07 - Heat a non-stick skillet over medium heat. Cook sandwiches for 3-4 minutes per side, pressing gently with a spatula until bread is golden brown and cheese is fully melted.
08 - Sprinkle with dried oregano, garlic powder, and remaining Parmesan during the final minute of cooking. Slice each sandwich in half diagonally and serve immediately with extra marinara sauce for dipping.